反应详情

A mixture of 41.7 g of 2,2-bis(fluoromethyl)-6-nitro-2H-1-benzopyran-4-carboxylic acid, 20 ml of sulfuric acid and 300 ml of ethyl alcohol was refluxed with heating for 6 hours. The reaction mixture was poured into ice water and crystals separated out were filtered to obtain 42.7 g of 2,2-bis(fluoromethyl)-6-nitro-2H-1-benzopyran-4-carboxylic acid ethyl ester with a melting point of 96°-98° C.

1. temperaturewas refluxed
2. temperaturewith heating for 6 hours
3. customseparated out
4. filtrationwere filtered